In a heat pump type refrigerating appliance which is widely used in an electric appliance such as an air conditioner, a heater and a water heater, HCFC-based refrigerant is conventionally used as refrigerant. However, the HCFC-based refrigerant having large ozone depletion potential is subject to CFCs control. Therefore, R410A (R32:R125=50:50) refrigerant which is HFC-based refrigerant having zero ozone depletion potential is generally used as alternative refrigerant of the HCFC-based refrigerant.
Under these circumstances, efforts are underway to arrest global warming on a world scale. Refrigerant makers, oil makers and air conditioner makers work toward further reduction and improvement of global warming potential (GWP), and work in research and development of new safe refrigerant and oil for new refrigerant.
Working toward such improvement, among the HFC-based refrigerants, R32 refrigerant is a next candidate refrigerant, and a compressor using the R32 refrigerant is proposed (see patent document 1 for example). The GWP of the R32 refrigerant is lower than that of R410A refrigerant, and COP (coefficient of performance) of the R32 refrigerant bears comparison with conventional refrigerants.